# Two point source

1. Jun 1, 2016

### rrosa522

1. The problem statement, all variables and given/known data
Two point sources, S1 and S2, are vibrating in phase and produce waves with a wavelength of 2.5 m. The two waves overlap at a nodal point. Calculate the smallest corresponding difference in path length for this point.

2. Relevant equations

3. The attempt at a solution
I really don't know how to start this question. How can I find the length when I am only given the wavelength

2. Jun 1, 2016

### rpthomps

What relevant equations do you think you would need?

3. Jun 1, 2016

### rrosa522

sinθn= (n-1/2) (λ/d) , honestly I really don't understand what this question is asking

Last edited: Jun 1, 2016
4. Jun 1, 2016

### rpthomps

Do you know what sources are, nodal points and the paths from the sources to the point on the nodal line?

5. Jun 1, 2016

yes

6. Jun 1, 2016

### rpthomps

There is a relationship which shows that the length of a line from a point on nodal line n, to source 1 and the length of another line from the same point on nodal line n, to source 2, when subtracted have a value dependent on the wavelength of the sources. Do you remember learning about path length difference?

7. Jun 1, 2016